Blockchain is incredibly emerging technologies in today's world. Now a days major issue faced by educational system is regarding fake documents, certificates. There are so many cases registered for the duplication of documents and all those cases go unnoticed. In this blockchain based system information stored is immutable it means it cannot be manipulated. Even if some attacker tries to manipulate the information present in the blockchain then hash value of the block gets changed. So, for this attacker has to recalculate the hash for the all the blocks in network, which is next to impossible. Thus, documents storage in blockchain provides high level security for the same. In this paper we have included various existing approaches for document security using blockchain platform and its benefits and limitations are also included so that one can get proper idea to rework or enhance the existing work with more advance technique. Also, we have highlighted problem of document storage and security enhancement issue in blockchain network.